FAQ

USB Flash Drives

How to format the USB to NTFS in Windows XP ?

These procedures will guide you to format your USB flash drive to NTFS in Windows XP:1. Right-click on my computer and then select manage to open device manager2. Open disk drive, right-click on the USB Flash Drive and then select properties3. Select policies tab, and then select optimized for performance4. Press OK5. The NTFS option shall be enabled in the Windows format.Note 1: About Windows default format tool, please refer to question 6

Why is the USB Flash Drive actual storage capacity slightly less that the product specification?

All storage products will display a lower than stated memory capacity. The reason is the general used method for calculation of megabyte used by manufacturers:

My USB Flash Drive has enough space, but why is the system showing an error message saying that the destination drive is full when I access a big file?

Generally, Microsoft windows operating system has 4 kinds of file system formats as NTFS, FAT, FAT32 and exFAT. Each file system format has different limitation for accessing one single file.

There are two following steps to help you analyze your problem:

Please check your file system format first

Please check if your files size fit limitation. If your file system format is FAT32, the limitation of one single file is 4GB; if your file system format is FAT, the limitation of one single file is 2GB.

If your single file size more than 4GB, please formatting your memory card to NTFS or exFAT file systems.

For caparison of above file format, please refer to question 2. If you can't find NTFS or exFAT option in Windows XP, please refer to question 1 or 8.

Why do I get a memory shortage message when I store files on the USB Flash Drive, even when the total capacity of files do not exceed the capacity of the USB?

This problem mostly occurs when the Flash memory is formatted by FAT format. With FAT format, if you try to copy or paste more that 255 files at one time you may receive an error message. To avoid this problem, you can format the USB flash drive with the FAT32 or NTFS format. If you need to use NTFS format, please refer to question 1.

How do I format my USB Flash Drive or other device on my computer?

Before format, please backup all your data and make sure you select the correct drive. Following steps will show you how to format your USB flash drive:

My USB Flash Drive works normally under Windows 2000 and XP, but in Windows Vista it fails, why?

If you use USB extension cable or USB Hub product, please remove your USB storage device from the USB port to make sure your device with enough working power. Following steps will help you update the driver under Vista:

If you still have problem with this, please refer to Microsoft Download Center to download the latest Hotfix to fix the problem, or you can contact us.

How do I know that my USB Flash Drive is correctly inserted into the USB port?

Please make sure your device is correctly inserted into the connector. If your computer still can't detect your device, please reverse the connector and insert it again.

If your computer detects your device, the first time driver installation process will be shown in the right corner of screen. If your computer device autorun function is enabled, the dialog window will show on the screen. Then you can choose which method you want to open your device. You also can use device manager to check your device status.

How can I safely move my USB Flash Drive in Windows systems?

The following steps will guide you to safely remove your USB flash drive:

Find the green arrow icon in the right corner of screen

Right-click on the icon, and select safety remove hardware

Select the USB flash drive you want to remove, mostly it shows with usb mass storage device, then select the usb mass storage after the massage dialog comes out.

Click ok.

Safety remove message will appear immediately in the right corner of screen.

Now can remove your USB flash drive from the USB port.

My USB Flash Drive was recognized by my computer, but it does not appear in My Computer, how do I access my USB ?

Another device may have been assigned with the same drive letter, therefore you have a drive conflict. If you want to solve this problem, please follow the instructions below to reassign USB Flash drive initial.

Reassign the drive letter to another one that is not used by another device.

Click on the ok to save your settings.

How do I remove computer virus from USB Disk?

All computer viruses including stored files will be erased after it had been formatted, but if the computer virus continues to be rewritten to the USB flash drive, we would like to recommend you to scan your computer with a virus scanner or any anti-virus program, once found please remove it immediately.

How do I prevent files from being damaged or lost from the USB Flash Drive?

We strongly recommend you to connect your USB flash drive to the rear side USB ports on your computer, and please avoid using an USB hub or extension cable.

Please do not use several USB devices at the same time to avoid the possibility of insufficient power supply.

Please make sure you use the safety remove option whenever you would like to disconnect USB Flash drive from your computer. You can refer to question 12 perform safety remove procedure.

The capacity of my USB Flash Drive has shrunken, what should I do?

If you receive this kind of message from your computer, please format your USB flash drive at first. Then check your USB Flash drive capacity again. If your problem still exist, please feel free to contact us, we'll help you to solve it.

Why does my USB Drive work on some computers, but not all ?

If USB flash drive worked on other computers, but not on yours, then the problem probably is within your system.

Below are some recommendations what will help you to solve this kind of problems:

If you had previously installed USB drivers for other devices, please remove them first. Enter your operation system safe mode and remove all unknown devices from device manager, it called universal serial bus controllers, then restart your computer in normal mode and then reconnect the USB flash drive.

If your computer is not USB 2.0 ready, please refer to the motherboard user guide to verify if your motherboard support USB 2.0 standard or not. In some cases, you will need to install the driver that is packaged with your motherboard driver CD. If you are using Windows operation system, please make sure that you have updated your system with the latest service pack version.

My computer only has USB 1.1 ports, may I use the USB Flash Drive?

USB 2.0 devices are backwards compatible with USB 1.1 and vice versa. However, when a USB 1.1 device (host or peripheral) is connected, it will only operate at USB 1.1 transfer rate.

What is the difference between USB 2.0 & USB 1.1?

A low-speed rate of 1.5 Mbit/s (~183 KB/s) is defined by USB 1.0. It is very similar to "full-bandwidth" operation except each bit takes 8 times as long to transmit. It is intended primarily to save cost in low-bandwidth human interface devices (HID) such as keyboards, mice, and joysticks.

A high-speed (USB 2.0) rate of 480 Mbit/s (~57 MB/s) was introduced in 2001. All hi-speed devices are capable of falling back to full-bandwidth operation if necessary; they are backward compatible. Connectors are identical.

Memory Cards

Why does the Memory Card have to be formatted before use?

Different electric equipments or operating system platforms may cause conflict when trying to store data within a non-native folder structure. In order to ensure the completeness and correction of the card, we suggest you format the card first before using it in any kinds of new devices.

Note: If you have questions about formatting your memory card, please refer to question 4.

Why is the actual storage capacity of the Memory Card slightly less that the product specification?

All storage products will display a lower than stated memory capacity. The reason is the general used method for calculation of megabyte used by manufacturers:

My Memory Card has enough space, but why is the system showing error message saying that the destination drive is full when I access a big file?

Generally, Microsoft windows operating system has 4 kinds of file systems formats: NTFS, FAT, FAT32 and exFAT. Each file system format has different limitation for accessing one single file.

The two following steps can help you to analyze your problem:

Please check your file system format first

Please check if your files size fit limitation. If your file system format is FAT32, the limitation of one single file is 4GB; if your file system format is FAT, the limitation of one single file is 2GB.

If your single file size more than 4GB, please format your memory card to NTFS or exFAT file systems.

How do I format my memory card on my computer?

Before format, please backup all your data and make sure you select the correct drive. Following steps will show you how to format your memory card:

Prepare a compatible memory card reader

Insert your card reader to computer USB port

Insert your memory card to your card reader

Double-click on my computer

Right-click on the reader associated with your memory card, then select format

If you need to format NTFS or exFAT file format, please refer to question 4.

I tried to write to the SD/SDHC card, but I got the error message the media is write protected. What can I do?

Please make sure that the write protection switch is on the correct unlocking position.

Please refer to the below picture.

My laptop ask me to install the driver after I insert the SD/SDHC card into the internal card reader.

This problem may be caused by the card reader. Please make sure your card reader supports the memory card you use and install the driver for the card reader correctly. You can obtain this information from the laptop guide book. If the situation continues, please contact the technical support center where you have purchased your laptop.

What is SD 2.0 (SDHC)?

SDHC (Secure Digital High Capacity, SD 2.0) is an extension of the SD standard which increases card's storage capacity up to 32 GB. SDHC cards share the same physical and electrical form factor as the older SD cards, allowing SDHC-devices to support both newer SDHC cards and older SD-cards. To increase addressable storage, SDHC uses sector addressing instead of byte addressing in the previous SD standard. The SD 2.0 standard limits the maximum capacity of an SDHC card to 32 GB. SDHC cards will not work in devices designed to the older SD 1.x specification. The SDHC trademark is licensed to ensure compatibility.

What is SDXC?

The Secure Digital Extended Capacity (SDXC) format was unveiled at CES 2009. The maximum capacity defined for SDXC cards is 2 TB (2048 GB). The older SDHC cards also have a maximum capacity of 2 TB based on the card data structures, but this is artificially limited to 32 GB by the SD 2.0 specification. The first SDXC being released are governed by an SD 3.0 specification (which also still specifies FAT32 format and thus lower capacities), whereas higher capacity and faster SDXC are expected to follow an SD 4.0 specification, which is due to be released in the spring of 2010.

What is the SDHC class rating ?

The speed class rating is the official unit of speed measurement for SDHC cards, which were defined by the SD Association. It is equal to 8 Mbit/s, and it measures the minimum write speeds based on the best fragmented state where no memory unit is occupied.

In Pretec CF card product definitions, 1x represent the performance of 150KBytes/sec. Take the 433x CF card as an example, the performance is 65MB/s (433 x 150KBytes/sec=65MBytes/sec).

All data transfer statistics provided is for your reference only. The actual speed of data transfer speed will depend on different system specifications, settings and performance.

What are the differences between CF type I, CF type II and CF I/O cards?

There are three subdivisions of CF cards, Type I cards, the thicker Type II cards and the I/O cards.

CF Type I At 43mm (1.7") x 36mm (1.4") x 3.3mm (0.13"), the CF Type I card's is less than one-half of a current PCMCIA Type II card. Compared to a 68-pin PCMCIA card, a CF card has 50 pins but still conforms to ATA specs.

CF Type II At 43mm (1.7") x 36mm (1.4") x 5.5mm (0.19"), the CF Type II card's is equal to that of a current PCMCIA Type II card. Compared to a 68-pin PCMCIA card, a CF card has 50 pins but still conforms to ATA specs.

Issues with data transfer speed mostly happens when using the SD, SDHC or COMPACT FLASH cards in a Cardreader connected to the computer. Usually the performance of the cardreader is slower than the memory card, therefore the correct choice of cardreader is critical.

The communication protocol between your card reader and the computer will determine the actual datatransfer rate:

USB 1.1 (Theoretical value speed up to 1.5MB/s)

USB 2.1 (Theoretical value speed up to 60MB/s)

PIO 1~6 (Theoretical value speed up to 25MB/s)

UDMA 1~6 (Theoretical value speed up to 133MB/s)

We strongly recommend, if you use high speed CF cards to use computer true IDE interface in order to ensure the best performance.

If you use high speed SDHC card, we recommend to use Pretec i-Disk reader II 233x to ensure the best possible performance.

Please check if your smart card chip have any damages or is scratched, this can cause the problem of reading.

Pease enter device manager to check card reader detected status.

Contact our technical support.

What is a smart card?

A smart card resembles a credit card in size and shape, but inside it is completely different. First of all, it has an inside- where a normal credit card is a simple piece of plastic. The inside of a smart card usually contains an embedded microprocessor. The microprocessor is under a gold contact pad on one side of the card. Think of the microprocessor as replacing the usual magnetic stripe on a credit card or debit card. The smart card applications could be; identity of the customer, library card, e-wallet, keys to various doors, etc... And only one card can be issued to an end-entity for all these applications. Smart cards hold these data within different files as you will read, these data is only visible to its program depending on the operating system of the card. To protect the consumer, businesses all around the world have invested in smart card with extensive online mainframe-based computer networks for verification and processing.

How can I safely remove my card reader in Windows operation systems?

The following steps will guide you how to safety remove your card reader:

Find the green arrow icon in the system task tray.

Right click on the icon and select safety remove hardware.

Select the USB flash drive you want to remove, mostly it shows with USB mass storage device, then select the USB mass storage after the massage dialog comes out.

Click ok.

Safety remove message will appear immediately in the right corner of screen.

You can remove your USB flash drive from the USB port now.

How do I confirm my smart card service activated in Windows operating systems?

In windows 2000 or XP, please enter control panel and click Administrative Tools, then click services, you will find a smart card services. Entering the smart card services to make sure it had been activated, if not, please to activate it.

In windows vista or 7, please enter control panel, click System and Maintenance, then click Administrative Tools, click services, you will find a smart card services inside. Entering the smart card services to make sure it had been activated, if not, please to activate it.

I use IE explorer for 34 in 1 smart card reader, and my card reader is detected by the webpage, but I still can't login – what can I do?

If your card reader and smart card is correctly inserted to your computer, most likely the problem is that the explorer Active scripting has been modified.

Please follow our procedure as below to solve your problem:

Enter control panel

Click internet properties

Click custom level

Find active scripting

Select enable

Click ok to save your settings

Reboot your computer

Why can't I use the ExpressCard SDXC Reader in my computer?

To use Pretec ExpressCard SDXC Reader you should install a driver on your operating system to obtain the best performance. The driver CD will included in the package.

SSD series

What is SSD?

A solid state drive (SSD) is a data storage device that uses solid-state memory to store persistent data. An SSD emulates a hard disk drive interface, thus easily replacing it in most applications. Recently, NAND based flash memory has become the standard for most SSD drive.

Most SSD manufacturers use non-volatile flash memory to create more rugged and compact devices for the consumer market. These flash memory-based SSD, also known as flash drives, do not require power. They are often packed in standard disk drive form factors (1.8, 2.5, and 3.5 inch). In addition, non-volatility allows flash SSD to retain memory even during sudden power outfall, and ensuring data persistence. SSD has no moving parts and short average seek times.

What is TRIM?

In computing, a TRIM command allows an operating system to inform a solid state drive (SSD) which data blocks, such as those belonging to a deleted file or affected by a format command, are no longer considered in use and can be wiped internally.

TRIM enables the SSD to handle garbage collection overhead, that would otherwise significantly slow down future write operations to the involved blocks. In the other hand, unlike with traditional hard disks, it would be advantageous to tell the SSD when you delete files so that the SSD could delete the pages at the time of the delete instead of performing the entire block erase procedure when you want to write data. This is where the TRIM function comes in.

Windows 7 and Windows Server 2008 R2 support the TRIM function, which OS use this function when they detect that a file is being deleted from an SSD. When the OS deletes a file on an SSD, it updates the file system but also tells the SSD via the TRIM command which pages should be deleted. At the time of the delete, the SSD can read the block into memory, erase the block, and write back only pages with data in them, as illustrated here. The delete is slower, but you get no performance degradation for writes because the pages are already empty, and write performance is generally what you care about.

TRIM only improves performance when you delete files. If you are overwriting an existing file, TRIM doesn't help and you'll get the same write performance degradation as without TRIM.

What is the difference between MLC and SLC?

SLC and MLC are both NAND-based non-volatile memory technologies. Multi-Level Cell (MLC) NAND and Single-Level Cell (SLC) NAND offer capabilities that serve two very different types of applications.

MLC NAND Flash allows each memory cell to store two bits of information, compared to the one bit-per-cell SLC NAND Flash. As a result, 90 nanometer (nm) MLC NAND offers a larger capacity (typically twice the density of SLC) and at a cost point appropriate for consumer products multi-function cell phones, digital cameras, USB drives and memory cards.

Though SLC NAND offers a lower density, it also provides an enhanced level of performance in the form of faster write speeds. Because SLC stores only one bit per cell, the likelihood for error is reduced. At 90 nanometer process, it is recommended to implement a 1 to 2-bit ECC for SLC, whereas 4-bit ECC is recommended on the MLC architecture. SLC also allows for longer write/erase cycle endurance and has a life expectancy rated at approximately 100,000 cycles, making it a better fit for use in applications requiring higher reliability, increased endurance and viability in multi-year product life cycles.

If I want to install an operating system on my SSD, do I choose MLC or SLC?

SLC SSD has better performance for small size data access and writes speed compared to MLC. Therefore, SLC SSD is recommended for installation of operating system purpose.

Is there any time limitation to the continuous use of the SSD?

Time between failures (MTBF) is estimated at 1,000,000 power-on hours.

What is ECC?

ECC (error correcting code) allows data that is being read or transmitted to be checked for errors. It differs from parity-checking in that errors are not only detected but also corrected. ECC is increasingly being designed into data storage and transmission hardware as data rates (and therefore error rates) increase.

Error-correcting codes are frequently used in lower-layer communication, as well as for reliable storage in media such as CDs, DVDs, HDDs, and RAM.

What is MTBF?

Mean time between failures (MTBF) is the predicted elapsed time between inherent failures of a system during operation. MTBF can be calculated as the arithmetic mean (average) time between failures of a system. The MTBF is typically part of a model that assumes the failed system is immediately repaired (zero elapsed time), as a part of a renewal process. This is in contrast to the mean time to failure (MTTF), which measures average time between failures with the modeling assumption that the failed system is not repaired.

Why is the actual storage capacity of the SSD slightly less than specified in your product specifications?

All storage products will display a lower than stated memory capacity. The reason is the general used method for calculation of megabyte used by manufacturers:

The ExpressCard module comes in two sizes. The ExpressCard/34 is 34 mm wide, while the ExpressCard/54 is 54 mm wide. The modules are both 5 mm high and 75 mm long. The 34 mm module has the advantage in that it can fit into the slot designed for the 54 mm card, but not versa. The ExpressCard simply slots into a USB interface that is already integrated on most desktop computers and notebooks.

System developers have welcomed the ExpressCard technology with open arms because of the number of benefits it offers. The cards pair expansion facility with higher performance, using less space. The technology also supports future implementations and high performance technology, and helps to drive down the cost due to standardization. The ExpressCard has gained support from most of today's leading technology manufacturers.

What is the difference between PCMCIA and ExpressCard?

The older PC Cards PCMCIA came in 16-bit and the later 32-bit CardBus designs.

The major benefit of the ExpressCard over the PCMCIA CardBus PC card is more bandwidth, due to the ExpressCard's direct connection to the system bus over a PCI Express x1 lane and USB 2.0, while CardBus cards only interface with PCI. The Express Card has a maximum throughput of 2.5 Gbit/s through PCI Express and 480 Mbit/s through USB 2.0 dedicated for each slot, while all CardBus devices connected to a computer share a total 1.06 Gbit/s bandwidth.

Industrial Products

I want to access a file bigger than 4GB, my disk has enough space, but why does the system show an error message telling that the destination drive is full?

Generally, Microsoft Windows operating system has 4 kinds of file system formats as NTFS, FAT, FAT32 and exFAT. Each file system format has different limitation for accessing one single file.

There are two following steps to help you analyze your problem:

Please check your file system format first

Please check if your files size fit limitation. If your file system format is FAT32, the limitation of one single file is 4GB; if your file system format is FAT, the limitation of one single file is 2GB.

If your single file size more than 4GB, please formatting your memory card to NTFS or exFAT file systems.

How can I affirm if my CF card is in fixed disk mode or removable disk mode?

Please Insert the CF card to the CF-To-IDE interface, if it is fixed disk mode, it will show "Hard Disk Drives"; if it is a removable disk mode, it will show "Removable Disk."

What is ECC?

ECC (Error correcting Code) is a method used to detect and correct errors introduced during storage or transmission of data.

What is the difference between Industrial CF cards and commercial CF cards?

PIO (Programmed Input/Output), is an old method transferring memory over IDE/ATA interface. The technique of a PIO involves is using the CPU, the drawback is that the CPU must mediate the transfer of data. But it's advantageous for the earlier designs machine because hardware implementation is simpler and adequate for devices that require low transfer rates.

What is DMA Mode?

DMA (Direct Memory Access), the transfer technique does not involve the CPU. The involved components move data directly to and from RAM, bypassing the CPU. Moreover, DMA can also be divided in two types, which are Multi-word DMA and Ultra DMA. The main difference between these two models is that Ultra DMA can serve faster data transfer speeds than Multi-word.

Why is my Mini IDE burned and melted?

There are several possibilities:

If the power cord was inserted in the wrong direction, it will cause VCC and GND short circuit. And then Mini IDE will fail to work.

There was a power surge.

The specific IxNxxx-xA Mini IDE design with power supply via IDE slot on motherboard, it is no need to connect extra power supply. Please make sure, don't connect external power cord to IxNxxx-xA Mini IDE device.

Can I use Pretec Mini IDE to boot-up my PC?

Yes, Pretec Mini IDE can be used as a bootable device. It has full capabilities and functions as a standard hard drive.

At what temperature range can the Pretec Mini IDE operate?

The IEMxxxMB-CP series support operating temperature is 0~70°C.

The IEMxxxMB-LR series support operating temperature is -20~85°C.

The IEMxxxMB-LR series support operating temperature is -40~85°C.

If I want to install OS (ex: Windows XP), should I then choose for PRO or ELITE series?

Pro series SSD has better performance for small size data access and writes speed compared to Elite series SSD. Therefore, Pro series SSD is recommended for use in operating system installation purpose.

What is the difference between ATA Flash card and Linear Flash card?

ATA Flash cards

Can be used interchangeably between any computer that supports the ATA or IDE. Computer that supports the ATA or IDE standard are independent of the host or operating system that it is used.

Linear Flash cards will work only on computers that have the same FFS System (Flash Filing System) Interoperability is limited.

Requires FFS (Flash File System) or FTL (Flash Translation Layer) software drivers for performance and compatibility and different versions of FFS or FTL drivers are not always compatible with different systems.

What significant features and advantages do Pretec ATA Flash card offer?

PC Cards (Linear Flash or SRAM) provide a type of memory on the card called Attribute memory. In which CIS card information is stored and where configuration registers are mapped. This information is later accessed by the PCMCIA framework during configuration and evaluated against platform hardware to determine the most appropriate configuration options for the card.

How to use SRAM card under Windows XP?

The following steps will show you how to use SRAM card under Windows XP:

Please update your Windows XP to Service Pack 3.

Insert the SRAM card into the PC Card slot

Your computer will detect your SRAM card as PCMCIA MTD-0000. The driver will be installed automatically.

Click the 'Yes' button when the warning dialog appears, to dismiss it.

Click 'Finish' when the 'Completing the found new hardware wizard' dialog appears.

Restart Computer.

Why can't I use Linear Flash card under Windows OS?

Microsoft Windows operating systems do not support FLASH file system (FFS) format, therefore the Linear Flash cards will not be recognized under Windows operating system. Linear Flash cards can be work only on computer that supports same FFS format.

About Us

Xstra Digital Storage B.V. is an innovative high-tech company providing Flash and DRAM storage products and solutions to enterprise, industrial, medical, automotive, aerospace and defense industries as well as to the consumer market.